Picker stick check strap



Dec. 12, 1950 F. B. WAKEFIELD 2,533,646

PICKER STICK CHECK STRAP Filed Sept. 5, 1947 la I I 1O 71 i i i '9 i i I l I 1 I l l l s Y i i l I H I CIZW' 16 1? gig? 14 l $5, 6 7, 6 5 4, INVENTOR. g fi m MY 5. WWI [H540 BY lifi swclwpu 25% Array/iffy.

Patented Dec. 12, 1950 UNITED STATES PATENT OFFICE PICKER STICK CHECK STRAP Frank B. Wakefield, Auburn, Maine Application September 5, 1947, Serial No. 772,321

2 Claims.

This invention relates to a picker stick check strap.

The object of the invention is to provide a novel and more endurable picker stick check strap than others now upon the market of which I am aware, and one which will maintain its useful life for relatively long periods of time.

With this general object in view and such others as may hereinafter appear, the invention consists of the picker stick check strap hereinafter described and particularly described in the claims at the end of this specification.

In the drawings illustrating the preferred. embodiment of the invention, Fig. 1 is a plan view and Fig. 2 is a side elevation of the preferred form of picker stick check strap embodying the invention, Figs. 3 and 4 are views similar to Figs. 1 and 2 illustrating an endless picker stick strap embodying the invention, Fig. 5 is a side elevation of the picker stick strap shown in Fig. 1 prior to its assembly in a loom and Fig. 6 is a cross sectional view taken on line 5-6 of Fig. 5.

In general the invention contemplates the provision of a picker stick check strap which is adapted for use upon the loom to check the movement of the picker stick in both directions. Prior to the present invention picker stick check straps have been made of leather, either single or double ply, and also of various composition materials including rubberized textile belting and the like In the operation of the loom when the picker stick is being checked in its movements after throwing or receiving the shuttle the picker stick check strap is subjected to the combined effect of shock and heavy strain. Ihe shock occurs upon impact of the picker stick with the strap and the stress and the strain result from the power utilized in the operation of the picker stick in throwing the sl uttle and also in receiving same.

In attempting to find materials which would possess useful lives beyond those of the ordinary leather check straps and treated textile check straps hereinbefore used, I have discovered that a picker stick check strap H3 may be produced which will out-wear all other picker stick check straps of which I am aware, by constructing the strap of a multi-ply construction wherein the inside ply I2 is made of grain leather which is tanned by a combination tanning process to produce a combination tanned leather as is well known in the art of tanning leather, such combination tanned leather being tanned by both combined chrome and vegetable tanning process. The grain leather strap forming the inner ply I2 is then buffed to remove the calendered surface for a purpose to be described. The outer ply I4 is made of a tough tanned leather, having high tensile strength, and in practice I have found satisfactory results may be secured utilizing a combination tanned leather having a calendered, dense, hard outer surface, and a non-calendered inner surface.

In producing the check strap shown in Fig. l, I prefer to utilize a layer it of water-proof cement for uniting the outer and inner plies. Such a cement may be obtained which is flexible and heat-resistant. I have experienced satisfactory results using the commercially obtainable heat resistant water-proof cements, preferably embodying a cellulose or Celluloid base, but it is to be understood that other known heat-resisting water-proof cements which are capable of firmly uniting leather surfaces may be used if desired. Most of such commercial waterproof cements comprise Celluloid cut with a solvent such as acetone. The outer and inner leather plies are united together under pressure either with or without heat, utilizing such a flexible Waterproof heat-resisting cement, and preferably the plies are united so that the inner surface of the inner ply comprises the surface of the combination tanned grain leather which has been buffed, and the outer or upper surface of the outer ply comprises the hard, dense, but flexible, calendered surface of th combination tanned grain leather above referred to.

After the laminated strap has been thus produced, the next step in the process of producing the improved check strap involves the impregnation of the inner ply, and preferably both the inner and outer plies, with a non-drying oil and preferably a neats-foot oi] composition embodying a major portion of neats-foot oil and a minor portion of Wax, such as paraffin, and a diluent in a small amount. In practice it is preferred to immerse the laminated straps in such an oil bath for a period of from 8 minutes to 12 minutes although the time of immersion will depend upon the gravity and density of the leather, and in any event sufiicient time should be permitted for the immersion so that the entire body of the laminated structure will be well impregnated. Other methods of impregnation may be employed if desired, Thereafter it is preferred that the impregnated straps be seasoned or mulled, and accordingly it is preferred to pile them in a moderately warm room for a period of days which may vary from one to several days 3 after which the straps are ready for shipment and use.

From the description thus far it will be observed that the present laminated structure of leather check strap embodies an outer leather ply which possesses high tensile strength as well as flexibility and durability. The inner ply while possessing strength and durability does not possess the high tensile strength of the outer strap and is' of a relatively'porous a nd yi'eldable cushicning nature such that in use under the impact of the picker stick the strap yields and compresses slightly, minimizing the effect ofthe shock. The interposed layer of water proof flexible heat-resisting cement connecting the yieldable inner or cushion memberofthe laminated structure to the outer more firm-andstrqng tensile ply serves to transmit to the outer ply the strain produced by impact of the picker -stick with the cushioning inner ply. The outer ply j' b'eing' relatively non-yiel'd'able" holds the st fucture in a firmpositionoif stting'anyperm-anent elongation and maintaining the-"check strap in the desired condition for effeotive operations for ielatively' long periods of time. Theoil im'pregant serves a mostuse-ful purpose not -only in prserv'mg the leather in' the desired yieldeble condition but also in lubricating-'the surface of r the inner-ply in its contactwith*the'picken'stick. This reduces to a minimum t'he burning-effect producedby the friction between-the pickerstick and the check strapand"further-preserves=the leather in a strong and '--dur'able= condition from "the deleterious efiects of the high humidity now used in mills. -Inaddition' the- 'complete impreg nation of the "entire 'check'strap'imparts ail-added degree of flexibility to-both theinner-and outer "plies thus contributing to--thelong life of --the check strap.

;Theutilityof-thepresen-t-strap maybe meas ured-in-some"degree by-experience with prior straps of oak tanned leather which-under '-the conditionsof high humidity of the present' day I mill last anywhere from two weeks to month. Applicants experience in "connec ion the present strap indicates entran eorupwards of sxifiontns'miar'esmparabr Eon'di tins.

' The p'resent invention may bee "bo'diedin a f'pi'ke'r'sftick check strap cffthel'inearltype such as i is illustrated in Figs. 1,2 and 'reieralbly' having 1 th 'iisuafs'l'ot's i l'found'therithi ouglfwhich the usual fastehingmeans r" if desired' be embod'iedin a: pi5ker" s.-lck heck strap ofthe-endless type asilliistratei in fi igs. 3 and 4,-wherein' the free-ends of the-strap' are unite'd heat rsis'ting water proof adh esive, at 20* or inother known manner." Such an endless Y Jcheck-sti'ap'"may-be secured in 'the'lo'om by' any 5 of the known'h'older's nowcomifionlyezriployed.

1 In recapitulation, it willbecbs'erVed that beclause of"the* hi'ghly humid -atni'ospheri(3* conditions of the 'presentday -mills wider *Which i the picker stick "check straps are used, and because of the severe'shocksand strains to which the same are subjected in present day high speed'looms, 'th'eextension of th'e' useful-life of check straps and the"reductionir'r-war'on the pickerstick are extremely important items in the expense of-- the loom upkeep.

'While many atteniptshave lieretofore been "made to attain these resultsynone so faras'ii' am ""e-ware"hav been successful. =B-y-' the cooperation of the outer ply of high tensile leather, for maintaining the shape, dimensions and resisting the strains, the inner ply of cushioning leather for absorbing the shock, the waterproof cement layer 5 for transmitting strains to the outer ply, and the oil impregnation of the inner ply to reduce to a minimum the burning efiect upon the check strap produced by the friction between the picker stick and the surface of the cushioning inner layer, I 10 have "produced a check-strap which experience seems 'toindica'te attains the dsired'results. The prior straps embodying oak tanned leather fail principally due to the burning of the leather, developing cracks under the heating effect developed from the friction between the picker stick and the strap. The porosity of the inner leather plyof the present strap serves as a reservoir for sufiicie'nt oil i'r'n'pregnant so that the surface -thereof is maintained lubricated during the use of the strap, thus reducing to a minimum the -'-=afores'aid friction and the heat developed.

While it is preferred to embody the invention in a two ply checkstrap, it is not desired to=limit the invention thereto. Havingthus described the-invention,--what is claimed is:

l. A flexible, shockabsorbing;:pickerstick check strap for looms; comprising: a laminated leather -strap having an-outer ply and an inner ply; both plies being ofsubstantial thickness said outer ply comprising a strap 0f tough -dense, calendered tanned'leather characterized byahigh tensile strengthand serving to prevents-undue stretching of the laminated leather strapumder the strain set up inchecking the movementof a loom 'picker stick-said innerply comprising a -strap of ahighly porouscompressible-..tanned grainleather, a-layer of cement between said -plies' permanently-bonding the innenply to the 40 outer ply toform a unitary structure, said inner ply being impregnated with a substantial body of oil of a non-drying naturedistributedthroiigh- ---out-'the interstices of the inner ply and forming in efiect a lubricant reservoir -fromlwhich said oil -ca-n be readilyexpressed through the poresof said A innerply to the-innersurface thereofby a'blow from a-picker stick, the substantial thickness, I porosity,-and compressibility of the innertply enabling it te yieldand be compressed substan- 5n tially upon impact by the picker stick t'o'cushion the shockofthe picker stick-on the check -s't'rap and to reduce-the strain transmittedthr'ough the bonding cement to-the outer'ply, thei mpact of 7 the pickerstickautomatically expressing oilffrom the porous innerply ontdthe inner Jsiirface' -thereof-to provide a sufficient'bil film between the inner surface of the inner: ply an'dthe surface of the picker" stick which engages therewith to reduce to aminir-num the developmnt'of "frictional heat therebet'ween when innse; thereby preventing burning; of the-checkstrap' and"c'ontributing to the long life thereof.

2. A flexible, shock absorbing picker stickcheck strap for looms, comprisingza laminated leather strap having an outer ply and an inner .ply, b'oth plies being of substantial thickness, said outer ply comprising-a strap of tough, dense,-"calendered tanned leather characterized ,by -high tensile strength-and serving to prevent-undue stretching 7oof-the laminated-leather strap under .the strain 1 set up in-checking the movement of a-loompicker stick, said inner ply-comprising a strap of highly porous compressible-tanned grain leather having the calendered innersurface thereof removed to impart-porosity thereto, a;.,layer of cement between said plies permanently bonding said inner ply to said outer ply to form a unitary structure, said inner ply being impregnated with a substantial body of oil of a non-drying nature distributed throughout the interstices thereof and forming in effect a lubricant reservoir from which oil can be readily expressed through the pores of said inner. ply to the inner surface thereof by a blow from a picker stick, the substantial thickness, porosity, and compressibility of the inner ply enabling it to yield and be compressed substantially upon impact engagement by the picker stick to cushion the shock of the picker stick on the check strap and to reduce the strain transmitted through the bonding cement to the outer ply, the impact of the picker stick automatically expressing oil from the porous inner ply onto the inner surface REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 1 Number Name Date 1,325,075 Byers Dec. 16, 1919 1,998,801 Brown Apr. 23, 1935 

